Training work 12. The system of evaluation of the examination paper in physics

TRAINING KIM № 031601

Unified State Exam
in PHYSICS

Work instructions

To complete the examination paper in physics, 3 hours are allotted

55 minutes (235 minutes). The work consists of two parts, including

31 tasks.

In tasks 1-4, 8-10, 14, 15, 20, 24-26, the answer is an integer or a final decimal fraction. Write the number in the answer field in the text of the work, and then transfer it according to the one below exemplary in answer form No. 1. Units of measurement of physical quantities do not need to be written.

The answer to tasks 5-7, 11, 12, 16-18, 21 and 23 is

sequence of two digits. Write your answer in the answer field in the text

work, and then transfer as below exemplary without spaces,

commas and other additional characters in the answer sheet No. 1.

The answer to task 13 is a word. Write your answer in the answer field

the text of the work, and then transfer according to the following exemplary in the form

answers number 1.

The answer to tasks 19 and 22 are two numbers. Write your answer in the answer field in the text of the work, and then transfer it according to the one below. pattern without separating numbers space, in the answer sheet No. 1.

The answer to tasks 27–31 includes a detailed description of the entire progress of the task. In the answer form No. 2, indicate the number of the task and

write down its complete solution.

When calculating, it is allowed to use a non-programmable

calculator.

All USE forms are filled in with bright black ink. It is allowed to use a gel, or capillary, or fountain pen.

When completing assignments, you can use a draft. Entries

in the draft are not taken into account when evaluating the work.

The points you get for completed tasks are summed up.

Try to complete as many tasks as possible and score the most

number of points.

We wish you success!

The following are reference data that you may need when doing your job.

Decimal Prefixes

Part 1

The answers to tasks 1-23 are a word, a number, or a sequence of numbers or numbers. Write down the answer in the answer field in the text of the work, and then transfer it to the ANSWER FORM No. 1 to the right of the number of the corresponding task, starting from the first cell. Write each character in a separate box in accordance with the samples given in the form. Units of measurement of physical quantities do not need to be written.

Spring rate 50 N/m. If with the help of this spring a box of mass 2 kg is evenly pulled along the floor, then the length of the spring increases from 10 to 15 cm. What is the force of friction of the box on the floor?

Answer: _______________________N

What is the wavelength of a 440 Hz sound wave in air?

Answer: _____________________m

The figure shows a graph of the dependence of the coordinate of the body on time.

Choose 2 true statements.

1) the acceleration of the body is 3 cm / s 2

2) body oscillation period 0.25 s

3) body oscillation frequency 0.25Hz

4) body oscillation period 2 s

5) body oscillation amplitude 3 cm

6) body oscillation amplitude 6 cm

In the school laboratory, they study the oscillations of a spring pendulum at various values ​​of the mass of the pendulum. If you increase the mass of the pendulum, how will it change: the frequency of its oscillations and the period of change of its potential energy?

1) increased

2) decreased

3) has not changed

Answer: ____________

Under what conditions do harmonic oscillations of a material point along a straight line and the movement of a body thrown at an angle to the horizon occur?

For each position in the first column, select the corresponding position in the second and write down to the table selected numbers under the corresponding letters.

PHYSICAL PHENOMENON

A) the material point performs 1) F resultant = 0

straight line harmonics

2) F result \u003d F heavy

B) the body is thrown at an angle to the horizon 3) g \u003d V 2 / R

air resistance is negligible 4) ma x = - kx

During isobaric heating of a monatomic gas in an amount of 2 mol, its temperature changed by 50 K. How much heat did the gas receive in the process of heat exchange?

Answer: _________________ J.

The pressure of an ideal gas at a constant concentration of its molecules decreased by 2 times. Choose two true statements.

1) The temperature of the gas has doubled.

2) Gas volume remains unchanged

3) The temperature of the gas has decreased by 2 times.

4) The volume of gas has doubled.

5) The number of gas molecules has doubled

In the process of compression of 1 mole of rarefied helium, its internal energy remains unchanged all the time. How does the temperature of helium and its pressure change in this case?

For each value, determine the appropriate nature of the change:

increases

decreases

does not change

Write in the table the selected numbers for each physical quantity.

Numbers in the answer may be repeated.

What is the direction of the electric field strength vector created by two identical opposite charges at the point O?

Answer: ___________

What charge must be imparted to two parallel-connected capacitors in order to charge them to a potential difference of 20,000 V if the capacitances of the capacitors are 2000 pF and 1000 pF.

Answer: ______________ Cl

A resistor is connected to the current source. How will the total resistance of the circuit, the current strength in it and the voltage at the terminals of the current source change if two more of the same are connected in series to the existing resistor?

increases

decreases

does not change

Write in the table the selected numbers for each physical quantity. Numbers in the answer may be repeated.

Establish a correspondence between physical quantities and units of measurement.

Write in the table the selected numbers under the corresponding letters.

A particle of mass m, carrying a charge q, flies at a speed into a uniform magnetic field with induction and moves along a circle of radius R. What will happen to the radius of the orbit and the period of revolution of the particle as its charge q increases?

For each value, determine the appropriate nature of the change: 1) increase

2) decrease

3) will not change

Write in the table the selected numbers for each physical quantity.

Numbers in the answer may be repeated.

A beam of orange light is refracted at an interface between two media, as shown in the figure. The measurements showed that the angles α and β are respectively equal

arcsin 0.5 and arcsin 0.6. Determine the ratio of the refractive indices of these media

Answer: ____

When a metal plate is illuminated with light of wavelength λ, the phenomenon of the photoelectric effect is observed. Select 2 true statements when the wavelength of light incident on the plate is reduced by 2 times.

Photon energy decreases by 2 times

The photon energy is doubled

The maximum kinetic energy of a photoelectron is doubled

The maximum kinetic energy of a photoelectron increases by more than 2 times

The maximum kinetic energy of a photoelectron decreases by less than 2 times

A grain of sand with a charge of 10 -11 C flew into a uniform electric field along its lines of force with an initial speed of 0.1 m / s and moved to a distance of 4 cm. What is the mass of a grain of sand if its speed increased by 0.2 m / s at a field strength of 10 5 V / m? Express your answer in milligrams (mg). Neglect the effect of gravity.

Answer: ______ mg

A beam of parallel light rays falls normally on a thin converging lens 6 cm in diameter with an optical power of 5 diopters (see figure). The screen is placed behind the lens at a distance of 10 cm. Calculate (in cm) the diameter of the light spot created by the lens on the screen

Answer: ______ cm

In the circuit shown in the figure, the voltmeter and ammeter can be considered ideal, and the current source has a finite resistance. Rheostat engine R moved, and the ammeter reading increased. Where did you move the rheostat engine and how did the voltmeter readings change? Justify the answer.

1 mole of an ideal monatomic gas was first cooled and then heated to an initial temperature of 300 K, increasing the gas volume by 3 times (see figure). How much heat was given off by the gas in section 1-2?

Electromagnetic radiation with a wavelength of 3.3 * 10 -7 m is used to heat water weighing 1 kg. How long will it take to heat water by 10 0 C if the source emits 10 20 photons in 1 second? Assume that the radiation is completely absorbed by water.

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Assessment system for examination paper in physics

Tasks 1–26

For the correct answer to each of the tasks 1–4, 8–10, 13–15, 19, 20, 22–26, 1 point is given. These tasks are considered completed correctly if the required number, two numbers or a word are correctly indicated.

Each of tasks 5-7, 11, 12, 16-18 and 21 is worth 2 points if

both elements of the answer are correctly specified; 1 point if one mistake is made;

0 points if both items are incorrect. If more than two are specified

elements (including, possibly, correct ones) or the answer

missing - 0 points.

27) The rheostat engine was moved to the left, the voltmeter readings dropped.

28) 85 s

29) 2500 J

30) 63 V

Option No. 3566832

Training work in physics 12/13/2017, variant PHI10203

When completing tasks with a short answer, enter in the answer field the number that corresponds to the number of the correct answer, or a number, a word, a sequence of letters (words) or numbers. The answer should be written without spaces or any additional characters. Separate the fractional part from the whole decimal point. Units of measurement are not required. In tasks 1-4, 8-10, 14, 15, 20, 25-27, the answer is an integer or a final decimal fraction. The answer to tasks 5-7, 11, 12, 16-18, 21 and 23 is a sequence of two numbers. The answer to task 13 is a word. The answer to tasks 19 and 22 are two numbers.

If the option is set by the teacher, you can enter or upload answers to the tasks with a detailed answer into the system. The teacher will see the results of the short answer assignments and will be able to grade the uploaded answers to the long answer assignments. The points given by the teacher will be displayed in your statistics.

A point body at rest begins to move along the axis Ox. The figure shows a projection dependency graph a x acceleration of this body with time t.

Determine the distance in meters that the body traveled in the third second of motion.

Answer:

On a smooth horizontal surface lie two bars connected by a light spring. To a bar of mass m= 2 kg apply a constant force equal in modulus F= 8 N and directed horizontally along the axis of the spring (see figure). Determine the elastic modulus of the spring at the moment when this bar moves with an acceleration of 1.5 m / s 2.

Answer:

A body with a mass of 4 kg, located on a rough horizontal plane, was reported along it with a speed of 10 m / s. Determine the modulus of work done by the friction force from the moment the body begins to move until the moment when the speed of the body decreases by 2 times.

Answer:

The stepped block has an inner pulley with a radius of 6 cm. Weights are suspended from the threads wound on the outer and inner pulleys as shown in the figure. There is no friction in the axis of the block. What is the radius of the outer pulley of the block if the system is in equilibrium? Express your answer in centimeters.

Answer:

On a body at rest, located on a rough horizontal plane, a horizontally directed force begins to act. The dependence of the modulus of this force F from time t shown in Figure 1. Figure 2 shows the corresponding dependence of the acceleration modulus a this body from t.

Choose two true statements based on the analysis of the graphs presented.

1) At a point in time t= 5 s modulus of friction force less than modulus of force F

2) At the moment of time t= 2 s friction force is 0

3) In the time interval (0 s) ≤ t 4) In the time interval (0 s) ≤ t F doesn't do work.

5) In the time interval (0 s) ≤ t

Answer:

A small piece of ice was lowered into a cylindrical glass of water to float, into which a piece of cork was frozen. After some time, the ice completely melted. Determine how the pressure force on the bottom of the glass and the water level in the glass have changed as a result of the melting of the ice.

1) increased;

2) decreased;

3) has not changed.

Answer:

A weightless spring is located on a smooth horizontal surface and is attached to the wall at one end (see Fig.). At some point in time, the spring begins to deform, applying an external force to its free end A and uniformly moving point A.

Establish a correspondence between the graphs of the dependences of physical quantities on the coordinates of point A and these quantities. For each position of the first column, select the corresponding position from the second column and write down the selected numbers in the table under the corresponding letters.

Answer:

When constructing the Réaumur temperature scale, it is assumed that at normal atmospheric pressure, ice melts at a temperature of 0 degrees Réaumur (°R), and water boils at a temperature of 80 °R. Find the average kinetic energy of the translational thermal motion of an ideal gas particle at a temperature of 91 °R. Express your answer in eV and round to the nearest hundredth.

Answer:

One mole of a monatomic ideal gas is involved in process 1 - 2, the graph of which is shown in VT-diagram. Determine for this process the ratio of the change in the internal energy of the gas to the amount of heat imparted to the gas.

Answer:

A blacksmith forges an iron horseshoe weighing 350 g at a temperature of 1100 °C. Having finished forging, he throws the horseshoe into a vessel of water. There is a hiss, and steam rises from the vessel. Find the mass of water that evaporates when a hot horseshoe is immersed in it. Consider that the water is already heated to boiling point. Express your answer in grams. (The specific heat capacity of iron is 460 J / (kg ° C), the specific heat of vaporization of water is 2.3 10 6 J / kg.)

Answer:

One mole of a monatomic ideal gas is involved in a cyclic process, the graph of which is shown in the TV diagram.

Choose two true statements based on the analysis of the presented graph.

1) The gas pressure in state 2 is greater than the gas pressure in state 4.

2) The gas work in section 2–3 is positive.

3) In section 1–2, the gas pressure increases.

4) In section 4–1, a certain amount of heat is removed from the gas.

5) The change in the internal energy of the gas in section 1−2 is less than the change in the internal energy of the gas in section 2−3.

Answer:

The figure shows a graph of the dependence of the volume V constant amount of an ideal gas from its absolute temperature T in process 1–2. Determine how the internal energy and pressure of the gas change in this process.

For each value, determine the appropriate nature of the change:

1) increased

2) decreased

3) has not changed

Write in the table the selected numbers for each physical quantity. Numbers in the answer may be repeated.

Answer:

Four point charges are fixed on a plane as shown in the figure. How is directed relative to the figure (to the right, to the left, up, down, towards the observer, away from the observer) the vector of the electrostatic field strength at the point O? Write your answer in word(s).

Answer:

Two resistors connected in series with resistances of 4 ohms and 8 ohms are connected to a battery, the voltage at the terminals of which is 24 V. What thermal power is released in a larger resistor?

Answer:

The figure on the left shows two flat mirrors (Z1 and Z2) and a beam horizontally incident on mirror 1. Mirror 2 is rotated about the horizontal axis passing through the point O by an angle of 15º (figure on the right). At what angle to the horizon will the ray reflected from mirror 2 propagate?

Answer:

The section of the electrical circuit is a series-connected silver and aluminum wires. A constant electric current of 2 A flows through them. The graph shows how the potential changes in this section of the circuit when it is displaced along the wires by a distance x. The specific resistances of silver and aluminum are 0.016 µOhm⋅m and 0.028 µOhm⋅m, respectively.

Using the graph, select two true statements and indicate their numbers in your answer.

1) The cross-sectional area of ​​​​aluminum wire is 7.84 ⋅ 10 -1 mm 2.

2) The cross-sectional area of ​​​​aluminum wire is 3.92 ⋅ 10 -1 mm 2.

3) The cross-sectional areas of the wires are the same.

4) The same thermal power is released in silver wire as in aluminum.

5) A thermal power of 8 W is released in the silver wire.

Answer:

Two small charged metal balls of the same radius are placed so that the distance between their centers is 2 a(see picture).

The balls are brought into contact and then parted to the same distance. How will the physical quantities indicated in the table change in this case? For each value, determine the appropriate nature of the change:

1) increase;

2) decrease;

3) will not change.

Write in the table the selected numbers for each physical quantity. Numbers in the answer may be repeated.

Answer:

The transformer is a closed core made of a special material, on which two coils are tightly wound. The first coil has 200 turns and the second has 1000 turns. An alternating voltage source with an amplitude of 10 V and a frequency of 100 Hz was connected to the terminals of the first coil. The outputs of the second coil are open (the transformer is not loaded). Establish a correspondence between physical quantities and their values ​​(in SI).

For each position of the first column, select the corresponding position from the second column and write down the selected numbers in the table under the corresponding letters.

Write down the numbers in response, arranging them in the order corresponding to the letters:

Answer:

Determine the number of protons and neutrons in the atomic nucleus of an unknown element X participating in a nuclear reaction Write down the number of protons and the number of neutrons together without punctuation marks between them.

Answer:

After a major radiation accident that occurred in 1986 at the Chernobyl nuclear power plant, some areas of the area were heavily contaminated with the radioactive isotope cesium-137 with a half-life of 30 years. In some areas, the maximum allowable content of cesium-137 was exceeded by 1000 times. After how many half-lives after contamination can such areas of the area again be considered as satisfying the norm? Round your answer to the nearest whole number.

Answer:

Establish a correspondence between the name of an elementary particle and the values ​​of its charge and mass numbers. In the table, the values ​​of the charge and mass numbers are separated by a double slash: charge number // mass number.

Write down the numbers in response, arranging them in the order corresponding to the letters:

Answer:

To control the strength of the direct current flowing in a section of the circuit, the following method is often used. A resistor is connected in series in the circuit section, the resistance of which is known with high accuracy (such a resistor is called calibrated), and the voltage across this resistor is measured.

The figure shows an image of a voltmeter scale, which measures the voltage across a calibrated 5 ohm resistor.

Assuming that the error of direct voltage measurement is equal to half the instrument division value, determine the current strength in the circuit section. In your answer, write down the value and the error together without a space.

Answer:

The student is required to determine the dependence of the period of free oscillations of a spring pendulum on the coefficient of spring stiffness. To do this, he prepared a tripod with a clutch and foot, a ruler with a millimeter scale, a load of known mass. Which two items from the list of equipment below should be additionally used to conduct this experiment?

In response, write down the numbers of the selected items.

1) wooden rail

2) beaker with water

3) a set of weights with unknown masses

4) set of springs

5) stopwatch

Answer:

The first star radiates 100 times more energy than the second. They are located in the sky so close to each other that they are visible as one star with an apparent magnitude of 5.

Based on this condition, choose two true statements.

1) If the second star is located 10 times closer to us than the first, then their apparent magnitudes are equal.

2) If the stars are located at the same distance, then the brightness of the first is 5 magnitudes, and the second is 0 magnitudes.

3) If these stars are located in space next to each other, then the second star is so dim that it is not visible to the naked eye, even if the bright first did not prevent this.

4) The first star is a white supergiant, and the second is a red supergiant.

5) The first star is necessarily hotter than the second.

Answer:

The speed of the current of a wide river is 3.6 km/h. At what angle to the direction of the river flow should the boatman direct the boat, whose speed relative to the water is 2 m/s, so that in 15 minutes it will be carried away in the direction of the current by 1.8 km?